What Is a Common Method for Sybil Resistance besides Quadratic Voting in DAOs?

A common method is the use of non-transferable, soulbound tokens (SBTs) or verifiable credentials tied to unique real-world identities. This attempts to link one on-chain identity to one unique person, making it harder for one entity to control multiple wallets for voting.

Another approach involves proof-of-humanity systems that use social graphs or biometric verification, though these often raise privacy concerns.